1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1983, 1988, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * $FreeBSD$
32 */
33
34#include "defs.h"
35#include "pathnames.h"
36#ifdef sgi
37#include "math.h"
38#endif
39#include <signal.h>
40#include <fcntl.h>
41#include <sys/file.h>
42
43__COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993 "
44	    "The Regents of the University of California."
45	    "  All rights reserved.");
46#ifdef __NetBSD__
47__RCSID("$NetBSD$");
48#include <util.h>
49#elif defined(__FreeBSD__)
50__RCSID("$FreeBSD$");
51#else
52__RCSID("$Revision: 2.31 $");
53#ident "$Revision: 2.31 $"
54#endif
55
56pid_t	mypid;
57
58naddr	myaddr;				/* system address */
59static char myname[MAXHOSTNAMELEN+1];
60
61static int verbose;
62
63int	supplier;			/* supply or broadcast updates */
64int	supplier_set;
65static int ipforwarding = 1;		/* kernel forwarding on */
66
67static int default_gateway;		/* 1=advertise default */
68static int background = 1;
69int	ridhosts;			/* 1=reduce host routes */
70int	mhome;				/* 1=want multi-homed host route */
71int	advertise_mhome;		/* 1=must continue advertising it */
72int	auth_ok = 1;			/* 1=ignore auth if we do not care */
73int	insecure;			/* Reply to special queries or not */
74
75struct timeval epoch;			/* when started */
76struct timeval clk;
77static struct timeval prev_clk;
78static int usec_fudge;
79struct timeval now;			/* current idea of time */
80time_t	now_stale;
81time_t	now_expire;
82time_t	now_garbage;
83
84static struct timeval next_bcast;	/* next general broadcast */
85struct timeval no_flash = {		/* inhibit flash update */
86	EPOCH+SUPPLY_INTERVAL, 0
87};
88
89static struct timeval flush_kern_timer;
90
91static fd_set fdbits;
92static int sock_max;
93int	rip_sock = -1;			/* RIP socket */
94const struct interface *rip_sock_mcast;	/* current multicast interface */
95int	rt_sock;			/* routing socket */
96int	rt_sock_seqno;
97
98
99static  int get_rip_sock(naddr, int);
100static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
101static void sigalrm(int s UNUSED);
102static void sigterm(int sig);
103
104int
105main(int argc,
106     char *argv[])
107{
108	int n, mib[4], off;
109	size_t len;
110	char *p, *q;
111	const char *cp;
112	struct timeval wtime, t2;
113	time_t dt;
114	fd_set ibits;
115	naddr p_net, p_mask;
116	struct interface *ifp;
117	struct parm parm;
118	char *tracename = 0;
119
120
121	/* Some shells are badly broken and send SIGHUP to backgrounded
122	 * processes.
123	 */
124	signal(SIGHUP, SIG_IGN);
125
126	openlog("routed", LOG_PID, LOG_DAEMON);
127	ftrace = stdout;
128
129	gettimeofday(&clk, 0);
130	prev_clk = clk;
131	epoch = clk;
132	epoch.tv_sec -= EPOCH;
133	now.tv_sec = EPOCH;
134	now_stale = EPOCH - STALE_TIME;
135	now_expire = EPOCH - EXPIRE_TIME;
136	now_garbage = EPOCH - GARBAGE_TIME;
137	wtime.tv_sec = 0;
138
139	(void)gethostname(myname, sizeof(myname)-1);
140	(void)gethost(myname, &myaddr);
141
142	while ((n = getopt(argc, argv, "isqdghmAtvT:F:P:")) != -1) {
143		switch (n) {
144		case 'i':
145			insecure++;
146			break;
147		case 's':
148			supplier = 1;
149			supplier_set = 1;
150			break;
151
152		case 'q':
153			supplier = 0;
154			supplier_set = 1;
155			break;
156
157		case 'd':
158			background = 0;
159			break;
160
161		case 'g':
162			memset(&parm, 0, sizeof(parm));
163			parm.parm_d_metric = 1;
164			cp = check_parms(&parm);
165			if (cp != 0)
166				msglog("bad -g: %s", cp);
167			else
168				default_gateway = 1;
169			break;
170
171		case 'h':		/* suppress extra host routes */
172			ridhosts = 1;
173			break;
174
175		case 'm':		/* advertise host route */
176			mhome = 1;	/* on multi-homed hosts */
177			break;
178
179		case 'A':
180			/* Ignore authentication if we do not care.
181			 * Crazy as it is, that is what RFC 1723 requires.
182			 */
183			auth_ok = 0;
184			break;
185
186		case 't':
187			new_tracelevel++;
188			break;
189
190		case 'T':
191			tracename = optarg;
192			break;
193
194		case 'F':		/* minimal routes for SLIP */
195			n = FAKE_METRIC;
196			p = strchr(optarg,',');
197			if (p && *p != '\0') {
198				n = (int)strtoul(p+1, &q, 0);
199				if (*q == '\0'
200				    && n <= HOPCNT_INFINITY-1
201				    && n >= 1)
202					*p = '\0';
203			}
204			if (!getnet(optarg, &p_net, &p_mask)) {
205				msglog("bad network; \"-F %s\"",
206				       optarg);
207				break;
208			}
209			memset(&parm, 0, sizeof(parm));
210			parm.parm_net = p_net;
211			parm.parm_mask = p_mask;
212			parm.parm_d_metric = n;
213			cp = check_parms(&parm);
214			if (cp != 0)
215				msglog("bad -F: %s", cp);
216			break;
217
218		case 'P':
219			/* handle arbitrary parameters.
220			 */
221			q = strdup(optarg);
222			cp = parse_parms(q, 0);
223			if (cp != 0)
224				msglog("%s in \"-P %s\"", cp, optarg);
225			free(q);
226			break;
227
228		case 'v':
229			/* display version */
230			verbose++;
231			msglog("version 2.31");
232			break;
233
234		default:
235			goto usage;
236		}
237	}
238	argc -= optind;
239	argv += optind;
240
241	if (tracename == 0 && argc >= 1) {
242		tracename = *argv++;
243		argc--;
244	}
245	if (tracename != 0 && tracename[0] == '\0')
246		goto usage;
247	if (argc != 0) {
248usage:
249		logbad(0, "usage: routed [-sqdghmAtv] [-T tracefile]"
250		       " [-F net[,metric]] [-P parms]");
251	}
252	if (geteuid() != 0) {
253		if (verbose)
254			exit(0);
255		logbad(0, "requires UID 0");
256	}
257
258	mib[0] = CTL_NET;
259	mib[1] = PF_INET;
260	mib[2] = IPPROTO_IP;
261	mib[3] = IPCTL_FORWARDING;
262	len = sizeof(ipforwarding);
263	if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
264		LOGERR("sysctl(IPCTL_FORWARDING)");
265
266	if (!ipforwarding) {
267		if (supplier)
268			msglog("-s incompatible with ipforwarding=0");
269		if (default_gateway) {
270			msglog("-g incompatible with ipforwarding=0");
271			default_gateway = 0;
272		}
273		supplier = 0;
274		supplier_set = 1;
275	}
276	if (default_gateway) {
277		if (supplier_set && !supplier) {
278			msglog("-g and -q incompatible");
279		} else {
280			supplier = 1;
281			supplier_set = 1;
282		}
283	}
284
285
286	signal(SIGALRM, sigalrm);
287	if (!background)
288		signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
289	signal(SIGTERM, sigterm);
290	signal(SIGINT, sigterm);
291	signal(SIGUSR1, sigtrace_on);
292	signal(SIGUSR2, sigtrace_off);
293
294	/* get into the background */
295#ifdef sgi
296	if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
297			   STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
298		BADERR(0, "_daemonize()");
299#else
300	if (background && daemon(0, 1) < 0)
301		BADERR(0,"daemon()");
302#endif
303
304#if defined(__NetBSD__)
305	pidfile(0);
306#endif
307	mypid = getpid();
308
309	/* prepare socket connected to the kernel.
310	 */
311	rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
312	if (rt_sock < 0)
313		BADERR(1,"rt_sock = socket()");
314	if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
315		logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
316	off = 0;
317	if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
318		       &off,sizeof(off)) < 0)
319		LOGERR("setsockopt(SO_USELOOPBACK,0)");
320
321	fix_select();
322
323
324	if (tracename != 0) {
325		strncpy(inittracename, tracename, sizeof(inittracename)-1);
326		set_tracefile(inittracename, "%s", -1);
327	} else {
328		tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
329	}
330
331	bufinit();
332
333	/* initialize radix tree */
334	rtinit();
335
336	/* Pick a random part of the second for our output to minimize
337	 * collisions.
338	 *
339	 * Start broadcasting after hearing from other routers, and
340	 * at a random time so a bunch of systems do not get synchronized
341	 * after a power failure.
342	 */
343	intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
344	age_timer.tv_usec = next_bcast.tv_usec;
345	age_timer.tv_sec = EPOCH+MIN_WAITTIME;
346	rdisc_timer = next_bcast;
347	ifinit_timer.tv_usec = next_bcast.tv_usec;
348
349	/* Collect an initial view of the world by checking the interface
350	 * configuration and the kludge file.
351	 */
352	gwkludge();
353	ifinit();
354
355	/* Ask for routes */
356	rip_query();
357	rdisc_sol();
358
359	/* Now turn off stdio if not tracing */
360	if (new_tracelevel == 0)
361		trace_close(background);
362
363	/* Loop forever, listening and broadcasting.
364	 */
365	for (;;) {
366		prev_clk = clk;
367		gettimeofday(&clk, 0);
368		if (prev_clk.tv_sec == clk.tv_sec
369		    && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
370			/* Much of `routed` depends on time always advancing.
371			 * On systems that do not guarantee that gettimeofday()
372			 * produces unique timestamps even if called within
373			 * a single tick, use trickery like that in classic
374			 * BSD kernels.
375			 */
376			clk.tv_usec += ++usec_fudge;
377
378		} else {
379			usec_fudge = 0;
380
381			timevalsub(&t2, &clk, &prev_clk);
382			if (t2.tv_sec < 0
383			    || t2.tv_sec > wtime.tv_sec + 5) {
384				/* Deal with time changes before other
385				 * housekeeping to keep everything straight.
386				 */
387				dt = t2.tv_sec;
388				if (dt > 0)
389					dt -= wtime.tv_sec;
390				trace_act("time changed by %d sec", (int)dt);
391				epoch.tv_sec += dt;
392			}
393		}
394		timevalsub(&now, &clk, &epoch);
395		now_stale = now.tv_sec - STALE_TIME;
396		now_expire = now.tv_sec - EXPIRE_TIME;
397		now_garbage = now.tv_sec - GARBAGE_TIME;
398
399		/* deal with signals that should affect tracing */
400		set_tracelevel();
401
402		if (stopint != 0) {
403			rip_bcast(0);
404			rdisc_adv();
405			trace_off("exiting with signal %d", stopint);
406			exit(stopint | 128);
407		}
408
409		/* look for new or dead interfaces */
410		timevalsub(&wtime, &ifinit_timer, &now);
411		if (wtime.tv_sec <= 0) {
412			wtime.tv_sec = 0;
413			ifinit();
414			rip_query();
415			continue;
416		}
417
418		/* Check the kernel table occasionally for mysteriously
419		 * evaporated routes
420		 */
421		timevalsub(&t2, &flush_kern_timer, &now);
422		if (t2.tv_sec <= 0) {
423			flush_kern();
424			flush_kern_timer.tv_sec = (now.tv_sec
425						   + CHECK_QUIET_INTERVAL);
426			continue;
427		}
428		if (timercmp(&t2, &wtime, <))
429			wtime = t2;
430
431		/* If it is time, then broadcast our routes.
432		 */
433		if (supplier || advertise_mhome) {
434			timevalsub(&t2, &next_bcast, &now);
435			if (t2.tv_sec <= 0) {
436				/* Synchronize the aging and broadcast
437				 * timers to minimize awakenings
438				 */
439				age(0);
440
441				rip_bcast(0);
442
443				/* It is desirable to send routing updates
444				 * regularly.  So schedule the next update
445				 * 30 seconds after the previous one was
446				 * scheduled, instead of 30 seconds after
447				 * the previous update was finished.
448				 * Even if we just started after discovering
449				 * a 2nd interface or were otherwise delayed,
450				 * pick a 30-second anniversary of the
451				 * original broadcast time.
452				 */
453				n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
454				next_bcast.tv_sec += n*SUPPLY_INTERVAL;
455
456				continue;
457			}
458
459			if (timercmp(&t2, &wtime, <))
460				wtime = t2;
461		}
462
463		/* If we need a flash update, either do it now or
464		 * set the delay to end when it is time.
465		 *
466		 * If we are within MIN_WAITTIME seconds of a full update,
467		 * do not bother.
468		 */
469		if (need_flash
470		    && supplier
471		    && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
472			/* accurate to the millisecond */
473			if (!timercmp(&no_flash, &now, >))
474				rip_bcast(1);
475			timevalsub(&t2, &no_flash, &now);
476			if (timercmp(&t2, &wtime, <))
477				wtime = t2;
478		}
479
480		/* trigger the main aging timer.
481		 */
482		timevalsub(&t2, &age_timer, &now);
483		if (t2.tv_sec <= 0) {
484			age(0);
485			continue;
486		}
487		if (timercmp(&t2, &wtime, <))
488			wtime = t2;
489
490		/* update the kernel routing table
491		 */
492		timevalsub(&t2, &need_kern, &now);
493		if (t2.tv_sec <= 0) {
494			age(0);
495			continue;
496		}
497		if (timercmp(&t2, &wtime, <))
498			wtime = t2;
499
500		/* take care of router discovery,
501		 * but do it in the correct the millisecond
502		 */
503		if (!timercmp(&rdisc_timer, &now, >)) {
504			rdisc_age(0);
505			continue;
506		}
507		timevalsub(&t2, &rdisc_timer, &now);
508		if (timercmp(&t2, &wtime, <))
509			wtime = t2;
510
511
512		/* wait for input or a timer to expire.
513		 */
514		trace_flush();
515		ibits = fdbits;
516		n = select(sock_max, &ibits, 0, 0, &wtime);
517		if (n <= 0) {
518			if (n < 0 && errno != EINTR && errno != EAGAIN)
519				BADERR(1,"select");
520			continue;
521		}
522
523		if (FD_ISSET(rt_sock, &ibits)) {
524			read_rt();
525			n--;
526		}
527		if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
528			read_d();
529			n--;
530		}
531		if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
532			read_rip(rip_sock, 0);
533			n--;
534		}
535
536		LIST_FOREACH(ifp, &ifnet, int_list) {
537			if (n <= 0)
538				break;
539			if (ifp->int_rip_sock >= 0
540			    && FD_ISSET(ifp->int_rip_sock, &ibits)) {
541				read_rip(ifp->int_rip_sock, ifp);
542				n--;
543			}
544		}
545	}
546}
547
548
549/* ARGSUSED */
550static void
551sigalrm(int s UNUSED)
552{
553	/* Historically, SIGALRM would cause the daemon to check for
554	 * new and broken interfaces.
555	 */
556	ifinit_timer.tv_sec = now.tv_sec;
557	trace_act("SIGALRM");
558}
559
560
561/* watch for fatal signals */
562static void
563sigterm(int sig)
564{
565	stopint = sig;
566	(void)signal(sig, SIG_DFL);	/* catch it only once */
567}
568
569
570void
571fix_select(void)
572{
573	struct interface *ifp;
574
575
576	FD_ZERO(&fdbits);
577	sock_max = 0;
578
579	FD_SET(rt_sock, &fdbits);
580	if (sock_max <= rt_sock)
581		sock_max = rt_sock+1;
582	if (rip_sock >= 0) {
583		FD_SET(rip_sock, &fdbits);
584		if (sock_max <= rip_sock)
585			sock_max = rip_sock+1;
586	}
587	LIST_FOREACH(ifp, &ifnet, int_list) {
588		if (ifp->int_rip_sock >= 0) {
589			FD_SET(ifp->int_rip_sock, &fdbits);
590			if (sock_max <= ifp->int_rip_sock)
591				sock_max = ifp->int_rip_sock+1;
592		}
593	}
594	if (rdisc_sock >= 0) {
595		FD_SET(rdisc_sock, &fdbits);
596		if (sock_max <= rdisc_sock)
597			sock_max = rdisc_sock+1;
598	}
599}
600
601
602void
603fix_sock(int sock,
604	 const char *name)
605{
606	int on;
607#define MIN_SOCKBUF (4*1024)
608	static int rbuf;
609
610	if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
611		logbad(1, "fcntl(%s) O_NONBLOCK: %s",
612		       name, strerror(errno));
613	on = 1;
614	if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
615		msglog("setsockopt(%s,SO_BROADCAST): %s",
616		       name, strerror(errno));
617#ifdef USE_PASSIFNAME
618	on = 1;
619	if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
620		msglog("setsockopt(%s,SO_PASSIFNAME): %s",
621		       name, strerror(errno));
622#endif
623
624	if (rbuf >= MIN_SOCKBUF) {
625		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
626			       &rbuf, sizeof(rbuf)) < 0)
627			msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
628			       name, rbuf, strerror(errno));
629	} else {
630		for (rbuf = 60*1024; ; rbuf -= 4096) {
631			if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
632				       &rbuf, sizeof(rbuf)) == 0) {
633				trace_act("RCVBUF=%d", rbuf);
634				break;
635			}
636			if (rbuf < MIN_SOCKBUF) {
637				msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
638				       name, rbuf, strerror(errno));
639				break;
640			}
641		}
642	}
643}
644
645
646/* get a rip socket
647 */
648static int				/* <0 or file descriptor */
649get_rip_sock(naddr addr,
650	     int serious)		/* 1=failure to bind is serious */
651{
652	struct sockaddr_in rsin;
653	unsigned char ttl;
654	int s;
655
656
657	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
658		BADERR(1,"rip_sock = socket()");
659
660	memset(&rsin, 0, sizeof(rsin));
661#ifdef _HAVE_SIN_LEN
662	rsin.sin_len = sizeof(rsin);
663#endif
664	rsin.sin_family = AF_INET;
665	rsin.sin_port = htons(RIP_PORT);
666	rsin.sin_addr.s_addr = addr;
667	if (bind(s, (struct sockaddr *)&rsin, sizeof(rsin)) < 0) {
668		if (serious)
669			BADERR(errno != EADDRINUSE, "bind(rip_sock)");
670		close(s);
671		return -1;
672	}
673	fix_sock(s,"rip_sock");
674
675	ttl = 1;
676	if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
677		       &ttl, sizeof(ttl)) < 0)
678		DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
679
680	return s;
681}
682
683
684/* turn off main RIP socket */
685void
686rip_off(void)
687{
688	struct interface *ifp;
689	naddr addr;
690
691
692	if (rip_sock >= 0 && !mhome) {
693		trace_act("turn off RIP");
694
695		(void)close(rip_sock);
696		rip_sock = -1;
697
698		/* get non-broadcast sockets to listen to queries.
699		 */
700		LIST_FOREACH(ifp, &ifnet, int_list) {
701			if (ifp->int_state & IS_REMOTE)
702				continue;
703			if (ifp->int_rip_sock < 0) {
704				addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
705					? ifp->int_dstaddr
706					: ifp->int_addr);
707				ifp->int_rip_sock = get_rip_sock(addr, 0);
708			}
709		}
710
711		fix_select();
712
713		age(0);
714	}
715}
716
717
718/* turn on RIP multicast input via an interface
719 */
720static void
721rip_mcast_on(struct interface *ifp)
722{
723	struct group_req gr;
724	struct sockaddr_in *sin;
725
726	if (!IS_RIP_IN_OFF(ifp->int_state)
727	    && (ifp->int_if_flags & IFF_MULTICAST)
728	    && !(ifp->int_state & IS_ALIAS)) {
729		memset(&gr, 0, sizeof(gr));
730		gr.gr_interface = ifp->int_index;
731		sin = (struct sockaddr_in *)&gr.gr_group;
732		sin->sin_family = AF_INET;
733#ifdef _HAVE_SIN_LEN
734		sin->sin_len = sizeof(struct sockaddr_in);
735#endif
736		sin->sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
737		if (setsockopt(rip_sock, IPPROTO_IP, MCAST_JOIN_GROUP,
738			       &gr, sizeof(gr)) < 0)
739			LOGERR("setsockopt(MCAST_JOIN_GROUP RIP)");
740	}
741}
742
743
744/* Prepare socket used for RIP.
745 */
746void
747rip_on(struct interface *ifp)
748{
749	/* If the main RIP socket is already alive, only start receiving
750	 * multicasts for this interface.
751	 */
752	if (rip_sock >= 0) {
753		if (ifp != NULL)
754			rip_mcast_on(ifp);
755		return;
756	}
757
758	/* If the main RIP socket is off and it makes sense to turn it on,
759	 * then turn it on for all of the interfaces.
760	 * It makes sense if either router discovery is off, or if
761	 * router discover is on and at most one interface is doing RIP.
762	 */
763	if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
764		trace_act("turn on RIP");
765
766		/* Close all of the query sockets so that we can open
767		 * the main socket.  SO_REUSEPORT is not a solution,
768		 * since that would let two daemons bind to the broadcast
769		 * socket.
770		 */
771		LIST_FOREACH(ifp, &ifnet, int_list) {
772			if (ifp->int_rip_sock >= 0) {
773				(void)close(ifp->int_rip_sock);
774				ifp->int_rip_sock = -1;
775			}
776		}
777
778		rip_sock = get_rip_sock(INADDR_ANY, 1);
779		rip_sock_mcast = NULL;
780
781		/* Do not advertise anything until we have heard something
782		 */
783		if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
784			next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
785
786		LIST_FOREACH(ifp, &ifnet, int_list) {
787			ifp->int_query_time = NEVER;
788			rip_mcast_on(ifp);
789		}
790		ifinit_timer.tv_sec = now.tv_sec;
791
792	} else if (ifp != NULL
793		   && !(ifp->int_state & IS_REMOTE)
794		   && ifp->int_rip_sock < 0) {
795		/* RIP is off, so ensure there are sockets on which
796		 * to listen for queries.
797		 */
798		ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
799	}
800
801	fix_select();
802}
803
804
805/* die if malloc(3) fails
806 */
807void *
808rtmalloc(size_t size,
809	 const char *msg)
810{
811	void *p = malloc(size);
812	if (p == NULL)
813		logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
814	return p;
815}
816
817
818/* get a random instant in an interval
819 */
820void
821intvl_random(struct timeval *tp,	/* put value here */
822	     u_long lo,			/* value is after this second */
823	     u_long hi)			/* and before this */
824{
825	tp->tv_sec = (time_t)(hi == lo
826			      ? lo
827			      : (lo + arc4random_uniform(1 + hi - lo)));
828	tp->tv_usec = arc4random_uniform(1000000);
829}
830
831
832void
833timevaladd(struct timeval *t1,
834	   struct timeval *t2)
835{
836
837	t1->tv_sec += t2->tv_sec;
838	if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
839		t1->tv_sec++;
840		t1->tv_usec -= 1000000;
841	}
842}
843
844
845/* t1 = t2 - t3
846 */
847static void
848timevalsub(struct timeval *t1,
849	   struct timeval *t2,
850	   struct timeval *t3)
851{
852	t1->tv_sec = t2->tv_sec - t3->tv_sec;
853	if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
854		t1->tv_sec--;
855		t1->tv_usec += 1000000;
856	}
857}
858
859
860/* put a message into the system log
861 */
862void
863msglog(const char *p, ...)
864{
865	va_list args;
866
867	trace_flush();
868
869	va_start(args, p);
870	vsyslog(LOG_ERR, p, args);
871	va_end(args);
872	if (ftrace != NULL) {
873		if (ftrace == stdout)
874			(void)fputs("routed: ", ftrace);
875		va_start(args, p);
876		(void)vfprintf(ftrace, p, args);
877		va_end(args);
878		(void)fputc('\n', ftrace);
879	}
880}
881
882
883/* Put a message about a bad system into the system log if
884 * we have not complained about it recently.
885 *
886 * It is desirable to complain about all bad systems, but not too often.
887 * In the worst case, it is not practical to keep track of all bad systems.
888 * For example, there can be many systems with the wrong password.
889 */
890void
891msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
892{
893	va_list args;
894	int i;
895	struct msg_sub *ms1, *ms;
896	const char *p1;
897
898	/* look for the oldest slot in the table
899	 * or the slot for the bad router.
900	 */
901	ms = ms1 = lim->subs;
902	for (i = MSG_SUBJECT_N; ; i--, ms1++) {
903		if (i == 0) {
904			/* Reuse a slot at most once every 10 minutes.
905			 */
906			if (lim->reuse > now.tv_sec) {
907				ms = NULL;
908			} else {
909				ms = ms1;
910				lim->reuse = now.tv_sec + 10*60;
911			}
912			break;
913		}
914		if (ms->addr == addr) {
915			/* Repeat a complaint about a given system at
916			 * most once an hour.
917			 */
918			if (ms->until > now.tv_sec)
919				ms = NULL;
920			break;
921		}
922		if (ms->until < ms1->until)
923			ms = ms1;
924	}
925	if (ms != NULL) {
926		ms->addr = addr;
927		ms->until = now.tv_sec + 60*60;	/* 60 minutes */
928
929		trace_flush();
930		for (p1 = p; *p1 == ' '; p1++)
931			continue;
932		va_start(args, p);
933		vsyslog(LOG_ERR, p1, args);
934		va_end(args);
935	}
936
937	/* always display the message if tracing */
938	if (ftrace != NULL) {
939		va_start(args, p);
940		(void)vfprintf(ftrace, p, args);
941		va_end(args);
942		(void)fputc('\n', ftrace);
943	}
944}
945
946
947void
948logbad(int dump, const char *p, ...)
949{
950	va_list args;
951
952	trace_flush();
953
954	va_start(args, p);
955	vsyslog(LOG_ERR, p, args);
956	va_end(args);
957	(void)fputs("routed: ", stderr);
958	va_start(args, p);
959	(void)vfprintf(stderr, p, args);
960	va_end(args);
961	(void)fputs("; giving up\n",stderr);
962	(void)fflush(stderr);
963
964	if (dump)
965		abort();
966	exit(1);
967}
968